ISNUMBER

Use the ISNUMBER function check if a value is a Number.

Use

ISNUMBER( value )
Returns TRUE if the value is a number.

Parameter	Required	Description
value	Yes	any text or choice value to test

Returns

Logical

Examples

Validation for Text-Based Numeric IDs

In an Output Validation Formula, you can use ISNUMBER to ensure that a user has entered a purely numeric value into a Text or Choice field. This is useful when a field is technically a "Text" data type to allow for leading zeros or specific formatting, but the specific entry must still represent a valid number.

• Formula: ISNUMBER(this)
• Logic: The keyword this refers to the data currently being entered in the capture widget. If the user enters "12345," the function returns TRUE (valid). If the user enters "A12345," the function returns FALSE (invalid), preventing the form from being submitted until corrected.

Conditional Form Visibility

You can use ISNUMBER within Conditional Logic to show or hide specific form elements based on the type of data provided in a previous step. This helps keep forms simple by only displaying relevant fields when certain criteria are met.

• Scenario: A reviewer should only see a "Financial Risk Assessment" section if a "ProjectID" captured in the Teams Trigger is purely numeric.
• Formula: ISNUMBER(@Trigger.out.ProjectID)
• Logic: The formula is applied to the Show when property of a Row or Content Block. If the ProjectID is "55021," the formula returns TRUE and the section appears. If the ID is "PROJ-ALPHA," the formula returns FALSE and the financial section remains hidden.

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Pro Tip: Because of the use of specific data types (unlike the un-typed data in standard Excel cells), ISNUMBER is primarily used to test Text or Choice values. If you need to perform calculations on a text value that passes the ISNUMBER test, you must first convert it to a formal Number data type using the VALUE function.